Abstract:

Fire danger rating systems are a crucial tool in modern forest fire management decisionmaking.This paper calculated the fuel moisture codes and fire behavior indices for Daxinganling region based on the local fire weather data used to assess forest fire danger during the 1987-2006 fire seasons.Maps of all The Canadian Forest Fire Weather Indexes (FWI) System values were created for days when fires occurred by using interpolation methodology to obtain FWI values for each fire site.Fire distributions on spatial and temporal were analyzed.The results showed that the forest fires in the Daxing’anling region occured mainly in deciduous coniferous forest (61.3%),grass (23.9%) and deciduous broad-leaved forest (8.0%).lightning was a main resource to light the fires for Daxing’anling region,accounting for 57.1% of the total fires.Most fires occured from April to June with high fire danger weather,such as high values of FWI,fine fuel moisture codes (FFMC) and initial spread index (ISI).The FWI classes of fire danger (i.e.,low to extreme) were reassessed for conditions found in China based on the comparison of the values found on fires.FWI ranges for low,moderate,high,very high,and extreme high fire danger classes were assigned as follows:0-2.5，2.6-10.0，10.1-18.0，18.1-31.0 and ≥31.1,respectively.The FWI System reflects the regional fire danger and can be effectively used in wildfire management.In 1987-2002 there were two fires seasons in spring and autumn respectively.However,the fire period merged into one continunous season from the spring to autumn in 2002-2006,probably due to the impact of climate change.Spring seasonal severity rating (SSR) showed a great fluctuation in 1987-2006,and summer SSR had an opposite trend of fluctuation to spring SSR.Monthly severity rating of October increased significantly from 2000 to 2006.

Key words: Canadian Forest Fire Weather Index System, Daxing'anling Region, forest fire danger